Canopy management through crop forcing impacts grapevine cv. ‘Touriga Nacional’ performance, ripening and berry metabolomics profile

Climate changes are speeding up the maturation of grapes in numerous areas world, including Mediterranean basin, but warmer temperatures often uncouple technical and phenolic maturity, resulting unbalanced wines. We tested efficacy crop forcing (CF) delaying cv. ‘Touriga Nacional’ vines Douro Region, their impacts on plant performance, berry quality attributes metabolome were also evaluated. In two consecutive seasons (2019 2020), CF was conducted 15 (CF1) 30 (CF2) days after fruit set by hedging growing shoots to five nodes removing summer laterals, leaves clusters. Results showed that while CF2 delayed ripening 51 till first autumn rainfall, which compromised optimal sugar ripeness, CF1 one month, both treatments severely impacted production, mainly CF1, reduced grapevine yield 90 %. The effect protecting against drought stress not evident, judging values leaf pre-dawn water potential measured along seasons. resulted berries with lower pH higher titratable acidity than controls, total phenolics content increased 48 % 2020. A UPLC–MS-based targeted metabolomic analysis relative abundance key metabolites like flavan-3-ols (i.e., catechin gallate 661 %), trihydroxylated anthocyanins delphinidin-3-O-glucoside 656 CF2) stilbenes (resveratrol 700 positive wine quality.